class_docstr: The minibatch MAC metric.
  This plugin metric only works at training time.
  
  This metric computes the MAC over 1 pattern
  from a single minibatch.
  It reports the result after each iteration.
  
  If a more coarse-grained logging is needed, consider using
  :class:`EpochMAC` instead.
code: def __str__(self):
      return "MAC_MB"
  
imports: from torch.nn import Module
  from typing import List, Optional
  from torch import Tensor
  from avalanche.evaluation import Metric, PluginMetric, GenericPluginMetric
label_desc: Use image node_id 2 for calling the MinibatchMAC obj's underlying member method code with example usage: obj.__str__() and returns: str